The number of injuries and fatalities associated with residential fires in which a mattress, upholstered article or other filled item was the first item ignited or where these products exacerbated a fire event has led to regulatory efforts to reduce the flammability of mattresses, upholstered articles and bedclothes used in homes and other occupancies.
The passage of Assembly Bill 603 by the California Legislature of Assembly on Aug. 13, 2001, required that all mattresses and sleep surfaces sold in the State of California since Jan. 1, 2005, meet an open flame resistance standard described in the state's Technical Bulletin #603 (TB 603). Regulation and enforcement of TB 603 have fallen to the state's Bureau of Home Furnishings and Thermal Insulation (BHFTI).
On, Feb. 16, 2006, the United States Consumer Products Safety Commission (CPSC) approved new a regulation for further reducing mattress flammability beyond the level required by the Cigarette Ignition Standards as codified in Part 1632 of the Code of Federal Regulations 16 (16 CFR 1632) (or formerly FF 4-72) since the 1970's. This regulation—16 CFR 1633—will be effective on Jul. 1, 2007.
Further, the CPSC is engaged in preparing and evaluating a bedclothes flammability standard as an adjunct to its mattress flammability work. This work has been announced in the Federal Register Advance Notice of Public Rule Making (ANPR) published Jan. 13, 2005 (Volume 70, Number 9 Page 2514) and is proposed as 16 CFR 1634.
The topic of “bedclothes flammability” is also under scrutiny by the State of California under the BHFTI Technical Bulletin #604 (TB 604) which is presently in draft form as published on Oct. 1, 2004, and pending final comment, revision, approval and enactment into law as of July 2005.
Both the CPSC and the BHFTI have been engaged in the process of evaluating improved degrees of furniture flammability performance. The BHFTI work is exemplified in its efforts to revise the testing requirements found in California Technical Bulletin #117 (TB 117). The present CPSC work initially commenced in 1994 with the publication of an Advanced Notice of Public Rulemaking (ANPR) to initiate regulatory proceedings under the Federal Flammable Fabrics Act (FFA) covering the principal fire risks to upholstered furniture; ignition by smoldering cigarettes and ignition by small open flame sources (e.g., lighters, matches and candles). In May 2005, the CPSC published a Staff Draft Standard for Upholstered Furniture Flammability in preparation for issuing a new ANPR on upholstered furniture flammability, which is expected to occur in 2006.
Numerous international and maritime standards also exist for the evaluation of mattresses, bedding sets, upholstered furniture and filled articles. Among these are British Standard (BS) 5852 Part 1, BS 5852 Part 2, BS 5852: 1990 Section 4, BS 5852: 1990 Section 5, BS 6807:1986, BS 7176, BS EN 1021-1, BS EN 1021-2, BS EN 597-1, BS EN 597-2, BS 7175, BS EN ISO 12952: Parts 1-4, International Maritime Organisation Method (IMO) A 652 (16) for upholstered furniture, and IMO A 652 (17) for bedding, as well as their material equivalents that have been adopted by various countries throughout the world.
The new standards for flammability of residential mattresses and upholstered furniture embodied in California TB 603, the revisions to California TB 117, the new 16 CFR 1633 regulation and the CPSC draft language on furniture have added to the realm of flammability testing protocols previously unavailable for the design of products targeted for institutional applications. Institutional settings, such as healthcare, dormitory and corrections, have used California Technical Bulletin #121 (TB 121), California Technical Bulletin #129 (TB 129), Boston Fire Department IX-11, ASTM E-1590, Underwriters Laboratory (UL) 1895, and National Fire Protection Association (NFPA) 267, to assess performance of full-scale composite mattresses and mattress foundations against open flame ignition sources.
California Technical Bulletin #133 (TB 133), ASTM E-1537 and NFPA 266 have been used to assess performance of full-scale composite furniture items and mock-ups against open flame ignition sources. NFPA 701, California TB 117, NFPA 260, NFPA 261, 16 CFR 1632, and UL 1975 have been used to assess small scale performance of component materials used in mattresses, furniture and filled articles against small open flames and smoldering cigarette ignition sources.
Institutional bedding installations typically require only a mattress and no foundation. Such mattresses usually comprise a solid core of polyurethane foam, latex foam or other foam composition, all of which may be combustion modified to some degree. Many of the components used in institutional mattresses and sleep support surfaces, including fill materials and covering fabrics, are subject to performance testing according to test criteria such as NFPA 701 and California TB 117.
Such requirements for full scale, open flame resistant performance in mattresses, mattress foundations, bedclothes, upholstered articles, and other similarly filled articles comprising resilient cushioning materials have created new demands for performance oriented fire barrier systems and related materials.
One approach to reducing flammability of mattresses, mattress foundations, upholstered furniture and other filled articles, such as bedclothes, has been to treat standard fabrics used in their construction with chemical flame retardants. These chemical flame retardants are employed to cause fuel loads, such as fabrics and fillings, to combust at heat levels higher than untreated materials. However, these chemical treatments may be objectionable because of distasteful odors which are noticeable when in close contact with the materials, off-gassing of obnoxious elements, stiffness of the treated fabric which may compromise the comfort of the finished mattress or mattress foundation, and the potential temporary durability of such treatments which may compromise the long term protection from open-flame, smoldering ignition and radiant/thermal heat flux sources.
Additional objectionable traits of such topically applied chemicals may be consumer backlash and rejection of such treatments, out of concern for the toxic effects of such treatments on human health. This was evidenced by the public reaction and subsequent regulatory control to findings of a flame retardant PBDE in human tissue and breast milk, and the potential adverse effects on the environment as the chemicals progress through the product life cycle from manufacturing through use and ultimate disposal.
Another approach has been to create fire barrier fabrics made from standard fibers that are chemically treated with flame retardants prior to their formation into yarns and/or fabrics or to use inherently flame retardant fibers for the formation of yarns and/or fabrics that do not require topical application of flame retardant chemicals. Such fire barrier fabrics essentially work by isolating a fuel load (foam, fiber, cushioning, resilient filling materials, etc.) from the ignition source. Chemically treated flame retardant fibers used in textile articles or chemically treated finished textile items may be non-durable or durable in nature.
The use of inherent flame retardant fibers in the design of fire barrier and thermal insulation textiles and related materials has shown to be both effective in terms of performance and in terms of the marketing attributes associated with them. Many of these fibers are, however, costly and their use in items such as mattresses, mattress foundations, upholstered furniture articles and other articles filled with resilient cushioning materials places a potentially high economic burden on consumers seeking to purchase such items.
The manufacturing processes of fibrous materials or the chemical treatment presently used in the fabrication of fire barrier materials is also costly—both in economic terms and in their potentially adverse environmental impact. The adverse environmental impacts arise from the consumption of non-renewable or limited available natural resources as well as the potentially toxic by-products and waste-products created by the manufacturing and treating processes.
Additionally, fiber based fire barrier textiles suffer from other potential limitations. In NIST (National Institute of Standard and Technology) Technical Note 1465: A Study of size effects in the Fire Performance of Beds (published January 2005), the entire contents of which are incorporated herein by reference, author Thomas Ohlemiller discusses fire barrier design methodologies in a Background Discussion of Fire Barriers that appears in the Note's Appendix A. Ohlemiller describes an ideal barrier design as being one that “would, at any point on its surface, never let enough heat through to the material inside to cause that material to gasify at all”, but he asserts that cost “will generally preclude such a heat impermeable barrier.” Preferred barrier material is described as having porosity but the pores must small enough to preclude “direct flame propagation” through the pores. The pore dimensions are described as “smaller than a millimeter or less”. Ohlemiller continues to observe that many barriers are based on fibers that “char when heated” but that these char formations are prone to oxidation during flame exposure, which “erodes” them.
However, none of the above approaches are capable of imparting sufficient and consistent flame-retardant characteristics to the full breadth of styles and constructions of bedding such as mattresses and mattress foundations, upholstered furniture articles, and other articles filled with resilient cushioning. As a result, a need exists for new materials to protect bedding, upholstered furniture articles, and other articles from fire that overcome at least one of the aforementioned deficiencies.